https://bookdown.org/rdpeng/RProgDA/reading-web-based-data.html
Methodology of flood estimation
I probably should have a wider list of design flood estimation methods in the hydro_extremes lecture
- Write the water balance to express \(Q(t)\), the total discharge at time t, as a function of \(Q_{gw}(t)\), the groundwater exfiltration and \(Q_{gl}(t)\), the glacier melt contribution (we neglect rain and evapotranspiration)
- \(Q(t) = Q_{gw}(t) + Q_{gl}(t)\)
- Write the solute mass balance to express \(Q(t) EC(t)\) (the mass of solutes exiting the catchment per second) as a function of \(Q_{gw}(t)\), \(Q_{gl}(t)\) as well as \(EC_{gw}\) and \(EC_{gl}\), which are respectively the constant electrical conductivity values for groundwater and glacier melt. EC is a proxy for the concentration of solutes in water.
- \(Q(t) * EC(t) = Q_{gw}(t)*EC_{gw} + Q_{gl}(t)*EC_{gl}\)
- By substituting \(Q_{gl}(t)\) in one of the previous equations, express \(Q(t)\) as a function of \(Q_{gw}(t)\), \(EC(t)\) and the constants \(EC_{gw}\) and \(EC_{gl}\)
- \(Q(t) = \frac{Q_{gw}(t)*(EC_{gw} - EC_{gl})}{EC(t) - EC_{gl}}\)
- Write the infiltration rate as a function of the storage volume and the exfiltration rate \(Q_{gw}\)
- We neglect evapotranspiration and recharge from rain
- \(Q_{inf}(t) = dV(t)dt + Q_{gw}(t)\)
- Remember what “downscaling” is?
- Downscaling adds small-scale details, like topography-induced variations, which are not seen on the GCMs larger grid
- Which parameters are affected?
- Air temperature
- Precipitation
- Relative humidity
- Wind speed
- Wind direction